Existing electronic door locks are used to provide access to different parts of a building or other facility. Such door locks provide entrance to a room, for instance, in response to a mechanical or electrical actuation of a bolt extending from a door which engages a receiving portion of a frame. Electronic door locks can be isolated individual devices or can be found in an electronic lock system which provides electronic communication between the electronic lock and a control system. Some electronic locks systems are hardwired to an interface device which monitors and controls the state of the electronic lock. Other electronic lock systems employ wireless electronic locks that communicate with a wireless interface device, also known as a panel interface module, sufficiently proximate to the electronic locks to enable radio communication. The interface device is configured to monitor and control the state of a predetermined number of electronic locks, such that multiple interfaced devices can be required in a facility of a large size, since one interface device can be insufficient to monitor and control all of the electronic locks in the facility. Consequently, a number of interface devices are hardwired to a central controller, also known as an access control panel, and are connected to the computer system of the facility. In some facilities, more than one access control panel can be required. The computer system provides updates to the electronic locks through this radio communication network.
In one configuration of a known lock system, a reed switch is used in the frame of the door to detect a magnet disposed in the door. The proximity of the magnet to the reed switch indicates when the door is open or closed. This information is available to the interface device and can be used by the computer system to determine a door closed or door open status of each of the doors in the electronic lock system. While this information is quite useful, additional information indicating a state of the door with respect to the door frame at other than a door closed or a door open position is desirable. For instance, the reed switch configuration cannot determine door sag, door frame rub, the presence of tailgaters. Consequently, what is needed is a method and apparatus to determine the status of one or more doors with respect to a door frame which overcomes the deficiencies of the reed switch system.